I want to add a component to an existing entity during execution

[Scarlet-2]

#[derive(Component)]
struct Person;

#[derive(Component)]
struct Name(String);

#[derive(Component)]
struct ToDelete;

fn add_name(mut commands: Commands) {
    commands.spawn((Person, Name("Matheus".to_string())));
    commands.spawn((Person, Name("Filipe".to_string())));
    commands.spawn((Person, Name("Lucas".to_string())));
}

fn print_names(query: Query<&Name, With<Person>>) {
    for i in query.iter() {
        println!("{}", i.0)
    }
}

fn insert_thigs(query: Query<Entity, With<Person>>, mut commands: Commands) {
    for i in query.iter() {
        commands.entity(i).insert()
    }
}

[rparrett]

I think that GitHub has dropped some bits of your code between angle brackets, which is making it difficult to figure out what the question is. Could you edit the post and paste your code again, but in triple backticks?

Like this:

```rust
// your code here
```

[Scarlet-2]

Ok, just made a edit

[rparrett]

Okay, so it looks like you've expanded on the basic example from the Bevy book with your own ToDelete component, and you'd like to add that to one of the entities at run time? You're actually very close.

fn insert_things(query: Query<Entity, With<Person>>, mut commands: Commands) {
    for entity in query.iter() {
        commands.entity(entity).insert(ToDelete);
    }
}

This would add ToDelete to every entity that also has a Person component. You could also query the Name component at the same time to single out a particular entity.

fn insert_things(query: Query<(Entity, &Name), With<Person>>, mut commands: Commands) {
    for (entity, name) in query.iter() {
        if name.0 == "Filipe" {
            commands.entity(entity).insert(ToDelete);
        }
    }
}

Or if you want, there's another Command that would actually delete the entity.

commands.entity(entity).despawn();

[Scarlet-2]

Thanks for the help!